1158: Rubber Sheet

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Rubber Sheet
It IS about physics. It ALL is.
Title text: It IS about physics. It ALL is.

[edit] Explanation

This comic refers to a common analogy used to explain how mass distorts space-time — a bowling ball resting on a sheet of rubber distorts the sheet due to its weight. The system has some qualitative features in common with gravity; it's often misused to show that "mass warps spacetime" (895: Teaching Physics).

The next part of the original analogy explains a black hole: the slope of the sheet becomes so deep that you can't climb out from the bottom any more, similar to a black hole, which even light can't escape from. However, the comic subverts the analogy, and the sheet becomes a trampoline instead.

The line "Imagining is fun!" is also a homage to Richard P. Feynman's "Fun to Imagine" Series of Interviews.

The title text also states that the rubber sheet, broken rope and our whole life is all about physics.

[edit] Transcript

[Beret guy is standing on a giant bowling ball on a rubber sheet. Megan is watching.]
Beret Guy: Imagine a giant bowling ball on a rubber sheet.
Beret Guy: The ball's weight makes a dent in the sheet.
[A rope is pulling the ball down into the sheet.]
Beret Guy: Now imagine a rope that pulls the ball down even further.
Beret Guy: ...Annnnd...
[Rope lets go. Ball is catapulted with Beret Guy on it.]
BOOOIING
Beret Guy: Wheee
[Beret guy and ball are falling back down.]
Megan: ...Oh. I thought this was about physics.
Beret Guy: Imagining is fun!
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Discussion

There is no rope in black hole analogy. On the other hand ... maybe one day this becomes common analogy for explaining some method of FTL travel ... -- Hkmaly (talk) 08:52, 9 January 2013 (UTC)

It is no rope - it is a rubber sheet seen from the side. Sebastian --178.26.121.97 14:01, 9 January 2013 (UTC)sorry, you meant the rope there ;-) Sebastian --178.26.121.97 20:18, 9 January 2013 (UTC)

Did you see the harmonics of the wave? I think there are four different ones in the third frame. Sebastian --178.26.121.97 14:01, 9 January 2013 (UTC)

- Two harmonics, two different phases of each. 123.237.156.13 15:56, 9 January 2013 (UTC)

It seems to me there should be a cross-reference to 895: Teaching Physics (and if I knew more about the conventions of this wiki I would be bold and add it myself... but I don't, so I won't.) --67.36.177.100 17:35, 9 January 2013 (UTC)

Furthermore, you could see the "BOOOIING" in this comic as an alternative to the "Boooooring" (only one-letter difference) at the end of 895: Teaching Physics : Instead of becoming boring after "...Annnnd..." cliffhanger, the demonstration becomes really fun. Anyone to add that point in the explanation if relevant ? --KoundelitchNico (talk) 09:36, 24 September 2014 (UTC)

I made a playlist of the mentioned "Fun to Imagine" series of videos:

https://www.youtube.com/playlist?list=PLBE6765CE680E701E&feature=mh_lolz
Deelkar (talk) 03:16, 10 January 2013 (UTC)
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